(Pocket) Colposcope for Use in Resource Limited Settings

(Pocket) Colposcope for Use in Resource Limited Settings

RESEARCH ARTICLE Design of a Novel Low Cost Point of Care Tampon (POCkeT) Colposcope for Use in Resource Limited Settings Christopher T. Lam1,4*, Marlee S. Krieger1,3,4, Jennifer E. Gallagher2, Betsy Asma4, Lisa C. Muasher5, John W. Schmitt5, Nimmi Ramanujam1,3,4 1 Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America, 2 Department of Surgery, Duke University, Durham, North Carolina, United States of America, 3 Center for Global Women’s Health Technologies, Duke University, Durham, North Carolina, United States of America, 4 Duke Global Health Institute, Duke University, Durham, North Carolina, United States of America, 5 Department of Obstetrics and Gynecology, Duke University, Durham, North Carolina, United States of America * [email protected] Abstract OPEN ACCESS Citation: Lam CT, Krieger MS, Gallagher JE, Asma B, Muasher LC, Schmitt JW, et al. (2015) Design of a Introduction Novel Low Cost Point of Care Tampon (POCkeT) Colposcope for Use in Resource Limited Settings. Current guidelines by WHO for cervical cancer screening in low- and middle-income coun- PLoS ONE 10(9): e0135869. doi:10.1371/journal. tries involves visual inspection with acetic acid (VIA) of the cervix, followed by treatment pone.0135869 during the same visit or a subsequent visit with cryotherapy if a suspicious lesion is found. Editor: Abhijit De, ACTREC, Tata Memorial Centre, Implementation of these guidelines is hampered by a lack of: trained health workers, reliable INDIA technology, and access to screening facilities. A low cost ultra-portable Point of Care Tam- Received: February 23, 2015 pon based digital colposcope (POCkeT Colposcope) for use at the community level setting, Accepted: July 27, 2015 which has the unique form factor of a tampon, can be inserted into the vagina to capture Published: September 2, 2015 images of the cervix, which are on par with that of a state of the art colposcope, at a fraction of the cost. A repository of images to be compiled that can be used to empower front line Copyright: © 2015 Lam et al. This is an open access article distributed under the terms of the Creative workers to become more effective through virtual dynamic training. By task shifting to the Commons Attribution License, which permits community setting, this technology could potentially provide significantly greater cervical unrestricted use, distribution, and reproduction in any screening access to where the most vulnerable women live. The POCkeT Colposcope’s medium, provided the original author and source are credited. concentric LED ring provides comparable white and green field illumination at a fraction of the electrical power required in commercial colposcopes. Evaluation with standard optical Data Availability Statement: All relevant data are within the paper and additional Supporting imaging targets to assess the POCkeT Colposcope against the state of the art digital colpo- Information files as well as via DukeSpace (http://hdl. scope and other VIAM technologies. handle.net/10161/10056). Funding: This work was supported by the National Institute of Health Quick Trials (Grant: Results 5R21CA162747-02 http://projectreporter.nih.gov/ Our POCkeT Colposcope has comparable resolving power, color reproduction accuracy, project_info_description.cfm?projectnumber= minimal lens distortion, and illumination when compared to commercially available colpo- 5R21CA162747-02) to NR. The funders had no role In vitro in vivo in study design, data collection and analysis, decision scopes. and pilot imaging results are promising with our POCkeT Colposcope to publish, or preparation of the manuscript. capturing comparable quality images to commercial systems. PLOS ONE | DOI:10.1371/journal.pone.0135869 September 2, 2015 1/22 Novel Low Cost POCkeT Digital Colposcope Competing Interests: NR has founded a company Conclusion called Zenalux Biomedical and she and other team members (MSK) have developed technologies The POCkeT Colposcope is capable of capturing images suitable for cervical lesion analy- related to this work where the investigators or Duke sis. Our portable low cost system could potentially increase access to cervical cancer may benefit financially if this system is sold screening in limited resource settings through task shifting to community health workers. commercially. For the concept of this system a provisional patent application was filed by CTL and NR with the title: COLPOSCOPES HAVING LIGHT EMITTERS AND IMAGE CAPTURE DEVICES AND ASSOCIATED METHODS. Number; PCT/US-14/ 67038 filed on 11/24/2014. This does not alter the Introduction authors' adherence to PLOS ONE policies on sharing data and materials. Invasive cervical cancer (ICC) affects the lives of 500,000 women worldwide each year, and results in more than 270,000 deaths [1]. More than 75% of ICCs occurs in Africa and India, with the highest incidence occurring in East Africa [2]. ICC is highly preventable by treating its precursor lesions and early stage cancers. However, these prevention services are not widely available in many low and middle-income countries (LMICs). Pap smear-based screening and HPV testing, which are widely available in western countries have not been feasible to imple- ment widely in LMICs owing to their cost, lack of infrastructure and appropriately trained human resources. Randomized controlled trials conducted in India and other LMICs have shown that visual inspection with acetic acid (VIA) is the most resource-efficient approach to screen for cervical cancer [3]. VIA is just a simpler version of colposcopy which is used in west- ern countries to diagnose cervical pre-cancer/cancer in women who have already been screened and found to have a positive Pap smear [4]. During colposcopy, the cervix is exposed using a speculum and visualized at low magnification (4-7X) for subtle features on the cervix [5, 6]. Whitening of the cervix from the application of acetic acid is use to determine the presence of lesions, through visualization of heterogeneity of suspicious regions (opacity, color, shape, pat- tern). A green filter can be applied to the colposcope’s illumination source to aid in the visuali- zation of vascularization, a known hallmark of severe dysplasia [5, 6]. The prohibitive cost of colposcopes (US$ 10,000–20,000) limits their uptake in resource-limited settings [7, 8]. There- fore, VIA is performed with a simple headlamp in most instances. VIA has several implementation challenges that limit the scale and hence, impact of this approach (1). Challenges include: 1) high screen positivity rates (likely due to inadequate train- ing and technology), leading to a high volume of patients being referred for follow up and at the same time, a very high loss to follow-up (about 50%) of the large number of screen-positive women [9]. If community health workers could be empowered to bring colposcopy to the pri- mary care setting and be trained to more effectively use this technology to triage women, sec- ondary and tertiary care facilities could focus their energies on managing priority patients who are in most urgent need of follow-up care, without being overwhelmed by women who don’t need treatment. Prior attempts to develop and implement low cost colposcopes for use in limited resource settings have met with some success. These include a low-cost hand-held portable analog col- poscope (Aviscope) [10–14], the Magnivisualizer [15–17], and the Family Health Ministries- Duke Portable Colposcope, which is based on surgical loupes. Prior low cost colposcope devices have had limited success stemming from: lack of digital image capture capability, fixed magnification, limited depth of focus, and poor illumination characteristics, [10–14]. A more recent system (Gynocular) has addressed some of these issues with the potential to have digital colposcopy capabilities [18, 19]. We have developed a novel, low cost Point of Care Tampon digital Colposcope (POCkeT Colposcope) to address many of the limitations described above for low cost colposcopes. The POCkeT Colposcope is shaped like a tampon and can be inserted and positioned such that it is PLOS ONE | DOI:10.1371/journal.pone.0135869 September 2, 2015 2/22 Novel Low Cost POCkeT Digital Colposcope 30–40 mm away from the cervix, obviating the need for high-end optics and high-resolution cameras used in state of the art colposcopes, which need to have a working distance of 300 mm. In fact, our POCkeT Colposcope leverages consumer grade light sources and cameras used in smart phones and 3D printing is used to create the tampon form factor. The POCkeT Colposcope’s images are comparable to that of a state-of-the-art digital colposcope by virtue of the fact that it is placed inside the vagina like a trans-vaginal ultrasound probe at a much closer working distance than a traditional colposcope. Frontline health workers trained to conduct VIA should be able to deploy the POCkeT Colposcope and obtain colposcopy images that will duplicate what is achievable with state of the art colposcopy. An Android operating system based phone/tablet coupled via the OTG (on-the-go) USB (universal serial bus) communica- tion protocol to the device allows digital images to be transmitted to tertiary centers and reviewed by expert physicians so that referrals are made for only those women who require treatment. The images along with the health worker and physician diagnosis and when avail- able, confirmatory biopsy can be uploaded to a database that can eventually be utilized as a vir- tual training tool for dynamic improvements in quality control and improve the quality of training of future health workers. Data can also be archived for retrospective or longitudinal studies. As HPV testing becomes more prevalent there is promise for wide spread screening for cer- vical cancer. However, VIA will still be a bottleneck in the recommended “see and treat” para- digm. A low cost ultra-portable digital colposcope system is essential to triage women and/or follow women who are HPV positive at the community level setting.

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